Power driven lawn mower



Feb. 13, 1934. H. J. STEGEMAN ET AL I POWER DRIVEN LAWN MOWER Filed Aug. 15, 1931 4 Sheets-Sheet 1 INVENTORS Feb. 13, 1934. H. J. STEGEMAN El AL 1,947,117

POWER DRIVEN LAWN MOWER Filed Aug. 15. 1931 4 Sheets-Sheet 2 INVENTORS.

ATTORN 5.

Feb. 13, 1934. l H. J. STEGEMAN El Al." 1,947,117

POWER DRIVEN LAWN MOWER Filed Aug. 15. 1931 4, Sheets-Sheet 3 WMa ,m

ATTORNEYS Feb.- 13; 1934. H. J. STEGEMAN El AL 1,947,117

POWER DRIVEN LAWN MOWER Fi'led Aug. 15. 1931 4 Sheets-Sheet 4 Patented Feb. 13, 1934 1,947,117

UNITED STATES PATENT/OFFICE POWER DRIVEN LAWN MOWER Henry J. Stegeman, Fairfield, and Sylvanus D. Locke, Bridgeport, Comn, assignors to The Locke Steel Chain Company, Bridgeport, Conn., a corporation of Connecticut Application August 15, 1931. Serial No. 557,238

36 Claims. (01. 56-26) This invention relates to a novel and improved to a bar 16 on the cutter, thus preventing translawn mower, particularly the type driven and verse movement of the cutter on the sub-frame, operated'by power. The novel features will be but permitting longitudinal. rocking movement, best understood from the following description it being understood that the word longitudinal and the annexed-drawings, in which we have is used herein as referringto the direction of shown a selected embodiment of the invention, travel and the word transverse is used to denote and in which:- adirection lateral to said direction of travel. The

Fig. 1 is a side elevation of a lawn mower sub-frame is mounted on a longitudinal pivot constructed according to the invention. 17 so that it may rock transversely with the 10 Fig. 2 is a fragmentary view similar to Fig. 1 cutter, and so that the cutter may accommodate but on an enlarged scale, parts being broken itself to unevenness in the ground. away and parts shown in section. The pivot 17 is shown as a push-rod extending Fig. 3 is a plan view of the structure shown in through alined openings in the bracket 6 of the. Fig. 2, parts being broken away and parts shown frame, these openings being formed in cars 18 and 5 in section. 19 on' the bracket. The rod is threaded into en- 7 Fig. 4 is a detail of the operating means for gagement with the ear 19 so that it will normally one of the clutches shown in Fig. 3. be held stationary, and so that it may be ad- Fig. 5 is a detail of the operating means for justed longitudinally, it being locked in adjustthe other clutch shown in Fig. 3. ed position by means of a nut 20. The forward 20 Fig. 6 is a view on an enlarged scale of one of end of the rodis shown as a ball 21, held in a the details appearing in Fig. 2. socket in the cutter, closely adjacent the trans- Fig. 7 is a plan view of the entire mower. verse center of the shoe 11 and beneath the Figs. 8, 9 and 10 are detail views illustrating stream of grass thrown back by the cutter. The the arrangement of the controlling means for the shoe being rigidly fastened to the cutter, the

motor and one of the clutches. push-rod is thus substantially connected direct- The invention is shown as embodied in a ma ly to the shoe, so as to push it forwardly without chine comprising a pair of ground-engaging rolls causing it to tip about either a longitudinal or a 1 and-2, supporting and connected by an axle 3. transverse axis. More specifically, there is prac- Pivotally supported on this axle is a frame 4 tically no tendency totip aboutalongitudinal axis 30 having a rearwardly extending bracket 5 and aextending through one end of the shoe, when the 35 forwardly extending bracket '6, this frame being mower is turning a corner, for example. The freely movable on the axle circumferentially ball and socket connection provides a longithereof. Supported on the bracket 5 is a motor tudinal pivotal connection, transverse to the pivot -7 and to the forwardly extending bracket 6 is 17, so that the cutter may rock transversely of 35 connected a cutter 8. This cutter may be of any the pivot 17 to accommodate itself to the ground.

=suitable type, here shown as of the type fully This same connection also permits an adjustshown and claimed in our copending application ment of the cutter to vary the height of cut, by Serial No. 299,658, now Patent No. 1,886,408. Furrocking the cutter on the shoe 11. This adjustther details of the cutter will therefore be omitted ment may be effected by loosely passing the plvexcept as they are material to an understandot or rod 1'7 through an openingin the sub-frame ing of our present invention." The cutter com- 14, as at 21', the rod at this point being providiprises a stationary knife 9 cooperating with roed with a bushing 221onger than the opening tating knives 10 forming part of the well-known and contacting at opposite. ends with washers reel common to lawn mowers. 23 held in place by nuts 24 threaded on the rod.

The stationary knife 9 is supported on a shoe Thecutter may be driven byachain 25 engaging 11 engaging the ground and hearing some of the a sprocket 26 on the end of the shaft of the rotatweight of the cutter, the motor 7 counterbalancing knives and a sprocket 2'7 on a drive shaft 28, ing the rest, so that the shoe engages the ground which is shown in the form' of a sleeve surroundwith relatively little force. Connected to the ing ashaft 29 mounted in suitable bearings on 50 bracket 5 is a framework 12 having a handle 13 the frame 4. The rotating knives move in a with which the operator may manipulate the counterclockwise direction as viewed in Figs. 1 mower, and on which he may bear down to still and 2, and so it will be seen that the lower stretch further relieve the pressure on the shoe. of the chain is the tight one while the upper The cutter 8 is mounted in a sub-frame 14 stretch is the slack one. The tight stretch is having transversely extending arms 15 pivoted arranged substantially parallel to the push rod 17, no

' whereby the force exerted by the chain, when operating the cutter, will be parallel to the longitudinal pivot ofthe cutter. This force then will have no component transverse to the pivot as viewed in Figs. 1 and 2, and so will not tend to cause rotation of the cutter on that pivot. For the same reason, when the cutter does rotate or rock on the pivot as the cutter passesover uneven ground, the force exerted by the chain resists that rocking and tends to return the cutter to position where the force acts parallel to the pivot.

The arrangement just described constitutes an improvement on that described and claimed in our copending application Serial No. 21,470, which has now matured into Patent No. 1,819,133 wherein the cutter is mounted on a longitudinal pivot,

' but wherein the driving means is not arranged with respect to the pivot as described above, to

ing 22 beyond the opening 21 being sufiicient under usual circumstances.

connection to the cutter permits the turning of the push rod. The nuts 24 will turn with the rod and carry with them the bushing 22, against which they are tightly set.' The bushing 22 will turn in the opening 21' of the frame 14. Thus the relation between the frame 14 and the pivot bar or push rod 17 will not be disturbed and the cutter unit will be carried forward or back without being tilted. If it is desired to vary the height of cut, this may be done by moving the nuts 24 and the associated bushing 22 along the rod. This will move the sub-frame 14 and with it the bar 16 to cause rotation of the cutter about the shoe 11. This adjustment will cause a slight raising or lowering of the sprocket 26, but not enough to materially affect the relation between the tight itlretch of the chain 25 and the longitudinal pivot The shaft 29 may drive the shaft or sleeve 28 by means of a clutch 30, which may be of the form shown in our copending application Serial No. 299,658, Patent 1,886,408, and which comprises a friction disk 31'splined on the shaft 29 and cooperating with a friction disk 32 fast on the sleeve 28. The disks are brought together or separated by a plurality of plungers 33 operated by levers 34 actuated by a cam 35 having conical surfaces sloping in opposite directions from a common circumference 36 defining a nose on the cam. The cam may he slid along the shaft and, as the nose passes the ends of the levers 34, the levers are thus prevented from moving back until the nose has passed them in the oppoite direc tion.

The clutch just described is thus used to con "trol the driving connection from the motor to the from the shaft 29 through a clutch 45 similar in The ball and socket construction to the clutch 30 and likewise operated by a cam 35 slidable on the shaft 29.

In practice, the cutter will usually be kept continually in operation for long periods of time, and therefore the clutch 30 controlling the driving connection of the cutter is operated by a simple hand or foot actuated lever 46 (Figs. 3 and 5) pivoted to a yoke 47 connected to the cam 35. The driving connection for the rolls 1 and 2, however, is usually made and broken more frequent-. ly, and therefore we provide means controlling the clutch 45 from the handle. This may be done by operating the cam 35 through a yoke 47 (Fig. 4) connected to the cam and actuated by a lever 48 pivoted at 49 and having an arm 50 in which is received the hooked end 51 of a rod 52 extending through a hollow post 53 forming part of the framework 12. The upper end of the rod 52 (Fig. 9) is connected to a lever, 54 pivoted at 55 and having a handle 56 depending from the handle 13. The parts are so arranged that when this handle 56 is moved forwardly, the clutch 45 will be thrown in, to cause forward movement of the mower, while a rearward movement of the same handle 56 will cause stoppage of that movement.

The motor may conveniently be controlled by a handle 57 pivoted gm the handle 13 and connected to a rod 58 leading through the framework to the motor to control the speed thereof.

The axle 3 is preferably connected to the rolls 1 and 2 by means of one-way ratchet drives, one of which is indicated in Fig. 2, as comprising pawls 59 cooperating with a ratchet 50 in a manner well known in the art. The use of these ratchet drives on the two rolls provides a differential driving connection therefor, so that the mower may readily turn corners.

While we have shown the invention as embodied in a specific form, it is, of course, understood that various changes in that form may be made without departing from-thespirit of the invention, and therefore we do not intend to limit ourselvesexcept by the appended'claims.

We claim:

1. In a power-driven lawn mower, ground-engaging rolls connected by an axle, a frame pivotally mounted and freely movable circumferentially of saidaxle and extending forwardly and rearwardly therefrom, a cutter mounted on said frame forwardly of said axle and comprising a ground-engaging shoe, a motor mounted on said frame rearwardly of said axle and counterbalancing' the weight of said cutter to partly remove said weight from said shoe, means to drive said rolls from said motor, and means to drive the cutter from the motor.

2. In a power-driven lawn mower, ground-engaging rolls connected by an axle, a frame pivotally mounted and freely movable circumferentially of said axle and extending forwardly and rearwardly therefrom, a cutter mounted on said frame forwardly of said 'axle on a longitudinal pivot and comprising a ground-engaging shoe, a motor mounted on said frame rearwardly of said axle and counterbalancing the weight of said 14! cutter to partly remove said weight from said shoe, means to drive said rolls from said. motor, and means to drive the cutter from the motor.

3. In a power-driven lawn mower, ground-engaging rolls connected by an axle, a frame pivotally mounted on-said axle and extending forwardly and rearwardly .therefrom, a cotter mounted on said frame forwardly of said axle on a longitudinal pivot and comprising a groundengaging shoe, a motor mounted on said frame frame forwardly of said axle on a longitudinal.

rearwardly of said axle and counterbalancing the weight of said cutter to partly remove said Weight from said shoe, means to drive said rolls from said motor, and means to drive the cutter from the motor, said driving means for the cutter being arranged to resist rocking of the cutter on the pivot while permitting said rocking.

4. In a power-driven lawn mower, ground-engaging rolls connected by an axle, a frame pivotally mounted on said axle and extendin wardly and rearwardly therefrom, a cutter mounted on said frame forwardly of said axle on a longitudinal pivot and comprising a ground-engaging shoe, a. motor mounted on said frame rearwardly of said axle and counterbalancing the weight of said cutter to partly remove said weight from said shoe, means to drive said rolls from said motor, means to drive the cutter from the motor, a pivotal connection between said pivot and the cutter extending transversely of the pivot, means for adjusting the cutter on said connection, and means for locking the cutter in adjusted position.

5. In a power-driven lawn mower, groundengaging rolls connected by an axle, a frame pivotally mounted and freely movable circumferentially of said axle and extending forwardly and rearwardly therefrom, a cutter mounted on said pivot and comprising a ground-engaging shoe, a motor mounted on said frame rearwardly of said axle and counterbalancing the weight of said cutter to partly remove said weight from said shoe, means to drive said rolls from said motor, means to drive the cutter from the motor, and a differential connection between said rolls.

' 6. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame extending forwardly and rearwardly of said shaft and freely pivoted thereon,

a cutter on said frame forwardly of said shaft and mounted on a longitudinally extending pivot, a ground-engaging shoe on said cutter, a. motor mounted on said frame rearwardly of said shaft, and means to drive said roll and said cutter from said motor.

7. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame extending forwardly and rearwardly of said shaft and pivoted thereon, a cut-,- ter on said frame forwardly of said shaft and mounted on a longitudinally extending pivot, 21. ground-engaging shoe on said cutter, a motor mounted on 'said frame rearwardly of said shaft, means to drive said roll and said cutter from said motor, a pivotal connection between said pivot and the cutterextending transversely of the pivot, means for adjusting the cutter on said connection, and means for locking the cutter in adjusted position.

8. In a power-driven lawn mower, a ground engaging roll having a transversely extending shaft, 8. frame mounted on said shaft and extending in the direction of travel of the mover, a cutter disposed forwardly of said roll and having a rotary knife and aground-engaging shoe, a push-rod extending in said direction and con.- nected to said frame and to said cutter to push the cutter from the frame, said rod being coni nected to said cutter at a point below the stream tending in the direction of travel of the mower,

a cutter disposed forwardly of said roll and having a rotary knife and a ground-engaging shoe, a push-rod extending in said direction and connected to said frame and to said cutter to push the cutter from the frame, said rod being connected to said cutter at a point below the stream line of the cut grass and forming a pivot on which said cutter may rock.

10. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mounted on said shaft and extending in the direction of travel of the mower, a cutter disposed forwardly of said roll and having a ground-engaging shoe, a sub-frame on which said cutter is mounted, a member extending in said direction of travel and connecting said sub-frame to said frame, and a universal connection between said sub-frame and said member.

11. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mounted on said shaft and extending in the direction of travel of the mower, a cutter spaced from said roll in said direction of travel and having a ground-engaging shoe, 2. sub-frame on which said cutter is mounted, a longitudinal pivot connecting said sub-frame to said frame, a pivotal connection between said pivot and the sub-frame extending transversely of the pivot, means for adjusting the sub-frame on said connection, and means for locking the sub-frame in. adjusted position.

12. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mounted on said shaftand extending in the direction of travel of the mower, a cutter spaced from said roll in said direction of travel and having a ground-engaging shoe, a sub-frame on which said cutter is mounted, a longitudinal pivot connecting said sub-frame to .said frame, a motor on said frame, means to drive of the pivot, means for adjusting the sub-frame on said connection, means for locking the subframe in adjusted position, a motor on said frame, means to drive the cutter from the motor, and

means to adjust the sub-frame with respect to the frame along said pivot.

14. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mountedon said shaft and extending in the direction of travel of the mower, a cutter spaced from said roll in said direction of travel and having a ground-engaging shoe, a sub-frame on which said cutter is mounted, a longitudinal pivotconnecting said sub-frame to said frame and threaded through an opening in said frame, and means to lock said pivot in said opening.

15. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mounted on said shaft and extending in the direction of travel of the mower,

a cutter spaced from said roll in said direction of travel and having a ground-engaging shoe. a sub-frame on which said cutter is mounted, a longitudinal pivot connecting said sub-frame to said frame and threaded through an opening in said frame, and means to lock said pivot in said opening, said pivot also passing freely an opening in the sub-frame.

16. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame mounted on said shaft andextending in the direction of travel of the mower, a

cutter spaced from said roll in said direction of travel and having a ground-engagingshoe, a subframe on which said cutter is mounted, a longitudinal pivot connecting said sub-frame to said frame and threaded through an opening in said frame, means to lock said pivot in said opening, said pivot also passing freely through an opening in the sub-frame, a bushing within said second opening and projecting from opposite ends thereof, and nuts threaded on said pivot against said opposite ends.

17. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter spaced from said roll in the direction of travel of the mower and comprising a stationary knife and a rotating knife, a motor mounted on said frame, a member for driving said rotary knife from said motor, and a push-rod connecting said frame and cutter and disposed substantially parallel to the direction of the driving force exerted by said member.

18. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter spaced from said roll in the direction of travel of the mower and comprising a stationary knife and a rotating knife, a motor mounted on said frame, a sprocket on said rotary knife, 3. chain engaging said sprocket and driven from said motor, and a rod connecting said frame to said cutter with a pivotal connection permitting rocking of the cutter transversely of the direction of travel, said rod being disposed substantially parallel to the tight stretch of said chain.

19. In a power-driven lawn mower, a ground engaging roll having a frame mounted thereon, a cutter disposed in front of said roll and comprising a stationary knife and a rotating knife, 2.

motor mounted on said frame, a pivotal connec tion between said frame and cutter extending in the direction of travel, a sprocket at one end of said rotary knife, a chain engaging said sprocket and driven from said motor, a ground-engaging shoe on said cutter, said pivotal connection being located on said cutter at a distance above the bottom of the shoe which is small compared to the length of said shoe transversely of the direction of travel.

20. In a power-driven lawn mower, a groundengaging roll and a cutter, a frame connecting said roll and cutter, a motor mounted on said frame and operatively connected to the roll and to the cutter, clutches controlling said connections, a handle extending rearwardly from said roll, a clutch-operating lever pivotally mounted on said handle, connections between said lever and said roll-controlling clutch constructed to cause engagement of said clutch upon forward movement of said lever, and other means to operate said cutter-controlling clutch.

21. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter spaced from said roll in the direction of travel of the mower and comprising a stationary knife and a rotating knife, a motor mounted on said frame, a connection from said frame to said cutter to move the cutter over the ground, said connection including a pivot extending in the direction'of travel and about which said cutter may rock transversely of said direction of travel, and a driving connection from the motor to the cutter, said connections being so related to each other as to resist said rocking of the cutter and when rock-ed to bring it back to normal position.

22. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame pivotally mounted and freely movable on said shaft circumferentially thereof and extending forwardly and rearwardly therefrom, a cutter mounted on said frame forwardly of said shaft and comprising a ground-engaging shoe, a motor mounted on said frame rearwardly of said shaft and counterbalancing the weight of said cutter to partly remove said weight from said shoe, said motor having a shaft, and means to drive either said roll or said-cutter or both from saidshaft.

23. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter disposed in front of said frame, and a member extending forwardly from said frame to said cutter to push the same over the ground as the roll rotates, said member being connected to said cutter by a ball and socket connection.

24. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter disposed in front of said frame, a member extending. forwardly from said frame to said cutter to push the same over the ground as the roll rotates, said member being connected to said cutter by a ball and socket connection, and means adjustably' holding said cutter against rotation on said connection on an axis transverse to the direction of movement of the cutter.

25. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter disposed in front of said frame, a member extending forwardly from said frame to said cutter to push the same over the ground as the roll rotates, said member being connected to said cutter by a ball and socket connection, means adjustably holding said cutter again rotation on said connection on an axis transverse to the direction of movement of the cutter, a motor on said frame, andadriving connection from said motor to said cutter so arranged with respect to said member as to resist rotation of the cutter on the ball and socket connection about an axis parallel to the direction of movement.

26. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon, a cutter disposed in front of said frame, and

. means to push said cutter from said frame comprising a rod disposed substantially at the transverse center of 'the cutter and pivoted thereto about a horizontal axis.

27. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon, a cutter spacedfrom said roll in the direction of travel of the mower, and means to move said cutter from said frame comprising a rod disposed substantially at the transverse center of the cutter and pivoted thereto with a ball and socket connection.

28. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon, a cutter disposed in front of said frame and having a ground-engaging shoe, a push-rod secured to the frame and to the cutter adjacent said shoe, and a sub-frame comprising a member pivotally connected to the push-rod and pivotally connected to the cutter at a point vertically spaced from the connection thereto of the pushrod.

29. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon, a cutter disposed in front of said frame and having a ground-engaging shoe, a push-rod secured to the frame and to the cutter adjacent said shoe, a sub-frame comprising a member pivotally connected to the push-rod and pivotally connected to the cutter at a point vertically spaced from the connection thereto of the push-rod, and means for adjusting said sub-frame along said push-rod for the purpose set forth.

30. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon, a cutter disposed in front of said frame and having a ground-engaging shoe, a push-rod secured to the frame and to the cutter adjacent said shoe, a sub-frame comprising a member pivotally connected to the push-rod and pivotally connected to the cutter at a point vertically spaced from the connection thereto of the push-rod, and means for adjusting said push-rod on said frame.

31. In a power-driven lawn mower, a groundengaging roll having a frame supported thereon,

a cutter disposed in front of said frame and having a ground-engaging shoe, a push-rod secured to the frame and to the cutter adjacent said shoe, a sub-frame comprising a member pivotally connected to the push-rod and pivotally connected to the cutter at a point verticallyspaced from the connection thereto of the push-rod, means for adjusting said push-rod on said frame, and

means for adjusting said sub-frame along said push-rod for the purpose set forth.

32. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a

a cutter disposed in front of said roll and comprising a stationary knife and a rotary knife, a ground-engaging shoe on said cutter, and a pivotal connection between said frame and cutter extending in the direction of travel, said pivotal connection being located on said cutter at a distance above the bottom of the shoe which is small compared to the length of said shoe transversely of the direction of travel.

33. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, 'a frame extending forwardly and rearwardly of said shaft and freely movable circumferentially thereof, a cutter on said frame spaced from said shaft in the direction of travel of the mower, a motor on said frame, and means to drive said roll and said cutter from said motor, said driving means being so arranged that said movement of the frame circumferentially of the shaft may occur without rotation of said roll.

34. In a power-driven lawn mower, a groundengaging roll having a frame mounted thereon, a cutter spaced from said roll in the direction of travel of the mower, a sub-frame on which said cutter is mounted, a member connecting said frame and sub-frame, and a universal connection between said sub-frame and said member.

35. In a power-driven lawn mower, a groundengaging roll having a transversely extending shaft, a frame extending forwardly and rearwardly of said shaft and pivoted thereon, a motor mounted on said frame rearwardly of said shaft, a cutter disposed forwardly of said shaft, and a universal connection between said frame and said cutter.

36. In a power-driven lawn mower, a groundengaging roll having, a transversely extending shaft, a frame extending forwardly and rearwardly of said shaft and pivoted thereon, a cutter on said frame forwardly of said shaft and mounted on a longitudinally extending pivot, a ground-engaging shoe on said cutter, a motor mounted on said frame, means to drive said roll and said cutter from said motor, a pivotal connection between said pivot and the cutter extending transversely ofthe pivot, means for adjustingthe cutter on said connection, and

means for locking the cutter in adjusted position.

HENRY J. STEGEMAN. SYLVANUS D. LOCKE. 

